Simplified Chaos has an insightful article about deciding when to use AIR and when to stick to browser-based Flash/Flex. His recommendation is to use the browser by default, and only move to AIR if you really need that desktop functionality. His reasoning, which I can agree with, is that people are much less likely to try out a desktop app that they have to install (and probably uninstall later) than to just look at something in a browser. I definitely agree — I hadn’t really realized it until reading this, but I’ve noticed that when I hear about a new AIR app then I always hope the web site has some screenshots or videos of the app in action, so that I don’t have to install it to try it out.

Keith Peters wrote a similar post on the same topic, which I also recommend.

(via Jesse Warden)

If you’re looking to simplify the local database access part of your AIR app, this might be the ticket. Brandon Ellis has written a no-frills wrapper class for AIR local database operations. The biggest benefit it provides is that if you add, delete, or update data in a table, it automatically updates whatever component is displaying the data from the related SELECT statement.

The part that caught my eye the most was that the wrapper class doesn’t dispatch any events to notify the view when the operations have completed. How, I asked myself, does it notify the view when the updated data loads? After a few seconds I realized the answer — it’s the magic of Flex data binding. The DataAccess class exposes the SELECT results as a property (dbResult) that’s a Flex ArrayCollection, and it’s marked [Bindable]. A Flex control can bind to that property as a data provider, and whenever the DataAccess instance reloads its data and updates the ArrayCollection. Then the Flex framework takes over, and the view gets updated automatically. Pretty slick; and it definitely saves a lot of event-handling code. So I guess seeing this in action gave me further appreciation for the power of data binding.

It has a couple of minor issues that I’ve noted in the comments on that page (but mostly they should be fairly easy to fix, if Brandon or someone else decides to do so).

(via: Greg Hamer)

I’ve been finishing up migrating my XML-RPC client library to ActionScript 3.0. First task, according to my own recommendation: write more unit tests.

Even though the unit tests I wrote for the ActionScript 2.0 version of the library used ASUnit, this time around I decided to go with the “home team” (i.e. developed by Adobe employees) solution and try out FlexUnit. Fortunately, at least for the tests I had already written, the two systems are pretty similar, so I only had a few tweaks to make to migrate them. (Too bad there wasn’t any way for me to unit-test my unit tests, to make sure they worked the same across frameworks.)

Anyway, along the way I found a couple of resources that were very helpful in getting started, especially since the FlexUnit documentation is rather sketchy (only limited API reference docs available). These were the articles that helped the most:

• Darron Schall: How to use FlexUnit with Flex Builder 2 (A great “getting started” article. This article was actually written while Flex Builder was still in public alpha, so it’s not perfectly accurate when describing Flex Builder’s dialog boxes — but it’s close enough that it was easy to figure out.)
• Daniel Rinehart: Asynchronous Testing with FlexUnit (Naturally, it doesn’t take long with ActionScript 3.0 before you want to test something involving events…so you need to do some asynchronous tests. The docs are no help here, and the included examples are really convoluted. I don’t know how Daniel figured it out, but I found his article very helpful for getting going with asynchronous tests.)

I just got a heads-up about a nice visualization component for Flex that draws links between a set of items. I’ve got an idea in mind which could use something like that, so it was nice and timely for me. So thanks, Mark Shepherd, Adobe Flex Builder engineer, for the component (and thanks to Bob Flynn, manager of the IUMMUG, for pointing it out to me).